1. Field of the Invention
This invention relates generally to horizontal frames which support motor vehicles and allow various pulling operations to be performed thereon. More specifically this invention relates to such frames which support motor vehicles, provide attachment points for securing a vehicle thereto and allow various kinds of pulling devices to be secured thereto such that pulling forces may be applied to a damaged section of a vehicle, thereby restoring damaged section to its original configuration.
2. Description of Prior Art
There are various forms of such machines typified by the patent issued to Rouis U.S. Pat. No. 3,518,867. However, in each of these devices the actual pulling force is applied through a pulling means secured to the vertical section of L-shaped member attached to the horizontal frame or towers either attached to the frame directly or anchored in the floor in a fixed relation relative to said frame.
The disadvantage is these prior art devices is that, in the case of the L-shaped member, the device must by some means, for example, a chain, bolt or clamp, by physically attached to the horizontal frame. This requires excessive additional time and effort because usually several pulling operations are required at different locations about the supported vehicle. In addition there is increased danger to the workmen using the equipment because they are required to crawl underneath the frame or extend their arms into the machine to make the required attachments. Where towers are employed the disadvantage lies in the fact that when in a fixed position relative to frame a pulling force may be required in a direction where no tower is available. Where movable towers are employed there exists the same difficulty as with the L-shaped member, namely the tower must be attached to the frame and requires additional time and effort and further results in increased danger to workmen because they are required to crawl underneath the frame or extend their arms into the machine.
In contrast, an object of the present invention is to eliminate any requirement for securing an L-shaped member to the horizontal frame and provides a construction wherein the normal forces required to allow the various pulling operations to be performed will also hold the L-shaped member or tower in a fixed position relative to the frame. Accordingly, there is no danger to workmen because they need not crawl under the machine nor do they need to extend their arms into the machine. Once the pulling chain or cable and the means for pulling such chain or cable is attached between the vertical section of the L-shaped member and the workpiece no further connections are necessary. Speed and ease of application are increased by elimination of an unnecessary step in the pulling process.
The prior art shows the horizontal frame constructed of longitudinal members spaced apart with fixed end members transverse to said longitudinal member, the entire structure forming a rectangle in a generally horizontal disposition. Also shown by prior art are adjustable transverse members which slide in slots in the longitudinal members or between double longitudinal members. The disadvantage lies in the fact that when these slots are in the longitudinal members, which are generally hollow, the necessary force, which can range as high as ten tons causes a distention of the slot and requires heavy construction of the longitudinal members to withstand such distention. Where double longitudinal members are used there is no distention but results in increased construction costs due to multiple member construction. Therefore, another object of the present invention is to show a simplified frame construction which provides the required strength without distention and supports at least one adjustable transverse member.
Further the prior art shows such frames in a fixed horizontal position requiring the vehicle to ascend a substantial incline. This is particularly difficult when such vehicle is damaged and cannot run under its own power. Therefore, it is an object of this invention to provide a frame machine which can be lowered at one end allowing the vehicle to be easily placed thereon. Some prior art teaches the lowering of one end of the machine as in the patent to Chisum U.S. Pat. No. 3,630,066, however, such construction is usually bulky and expensive requiring multiple lifting devices to return it to the horizontal. Further, such prior art devices rely on the lifting devices to maintain the horizontal position thereby increasing the danger to workmen by premature tilting of the machine should a lifting device fail.
Accordingly, it is another object of this invention to provide an inexpensive simplified lifting means that will not only allow tilting of the horizontal frame but will also provide a rigid support for holding the frame in a horizontal position.
The prior art further teaches construction of such frames comprising a plurality of front transverse members so as to allow anchoring of the vehicle irrespective of vehicle length. The disadvantage of such devices is that because the transverse members are in a fixed position many such members spaced longitudinally of the frame are required in application resulting in increased cost. Further, difficulty in application results where anchoring or jacking is required in a solely vertical direction because the vehicle itself must be properly positioned. An object of the present invention is to provide a simplified structure having an upper transverse member which is adjustable, at one end and like the previously described transverse members will not cause distention of slots in the longitudinal members. Also increased safety is an objective in that adjustment of the upper transverse member may be made without having the workman extend his arms into the machine due to the novel means of attachment of the upper transverse member to the longitudinal member.